Stoker furnace



T. A. MARSH STOKER FURNACE March- 8 1927- Filed Jan. 29. 1923 2 Sheets-Sheet 1 1 I fi weni or' T/zmaglflam/z.

. 1,620,270 March 8 1927' T. A. MARSH s'poKER FURNACE Filed Jan. 29. 1923 2 Sheets-Sheet 2 Patented Mar. 8,1927. p

- UNITED s-TA TES PATENT OFFICE.

THOMAS A. MARSH, OF CHICAGO, ILLINOIS, ASSIGNOR TO GREEN ENGINEERING COM- PANY, OF EAST CHICAGO, INDIANA, A CORPORATION OF ILLINOIS.-

STOKER FURNACE.

Application filed January 29, 1923. Serial No. 615,485.

This invention relates to chain grate stokers and consists in the matters hereinafter described and more particularly set forth in the appended claim.

In the accompanying drawings- Fig. 1 is a longitudinal vertical sectional View of a Stoker furnace embodying the features of my invention; and

Fig. 2 is a transverse vertical sectional view taken on line 22 of Fig. 1. In the drawings, I have shown a furnace equipped with achain grate 1 having upper .and lower runs or leads 2 and 3. Said grate 1 extends into the combustion chamber of the furnace through the front wall of its setting with the rear or tail end of the grate terminating short of the bridge wall 4 to provide a vertical ash discharge passage as in furnaces of this general kind. At the front of the furnace is a fuel hopper 5, through which fresh or green fuel is fed on the upper lead 2, which carries the fuel in a layer through the combustion chamber, as apparent.

The grate 1 extends horizontally between the side walls 6, 6 of the furnace setting, as shown in Fig. 2, and each of these walls includes a plurality of upright metal stools 7, 7. The stools 7, 7, in each wall, are laterally spaced apart the same distance with the stools in one wall aligned with the corresponding stools in the opposite wall. The stools 7, 7 rest on the foundation 8 of the furnace setting. Extending between and secured to the stools in each wall are housings or casings 9. These form with the stools between which they extend vertical air ducts 10 at the sides of the grate l, as shown in Fig. 2.

The space between the grate leads 2, 3 is divided into a plurality of compartments 11, 11, equal in number to the ducts 10 at one side of the grate. These compartments open at their ends into the ducts 10, 10. The compartments 11 are formed by cross-members 12, 12 aligned with and supported by the associate stools. Skids or rails 13, 13 extend lengthwise 'of the upper lead 2 beneath the same and support said upper lead. Said skids are supported by the cross-members 12, 12. Air seals between the compartments 11, .11 along the upper and lower edges of the cross-members 12, 12 are formed by shoes 14', 15, associated with said members 12 and bearing against the respective leads draft thereto.- Hinged dampers 20, 20 regulate the su l of the conduit To catch the siftings and droppage caught by the lower lead 3 and passed through its openings, I provide a plurality of collecting" hoppers 21, 21 beneath the lower lead, as shown in Fig. 1. These hoppers 21,21 are so arranged that there is a hopper below each compartment 11. The hoppers have discharge chutes 22, 22 and these lead to the ash collecting chamber be low the furnace and may be provided with suitable control gates 22, asshown. The hoppers 21, 21 are in the main supply couduit 19, but the forced draft therein is pre vented from reaching the compartments 11, 11 through the lower lead 3 from below by the hoppers having their walls close the compartments below said lower lead. This may be done by having the front and rear wa ls of the hoppers extended to the crossbeams 17, 17 and their. side walls secured to plates 23, 23 above the dampers 20, as shown in Fig. 2.

The main conduit 19 may be supplied with air in any suitable manner to deliver forced draft to the ducts 10. The means shown in Fig. 1 includes an electric motor 24 operating a blower 25, which opens into the conduit 19 through its front wall 26. The latter may be aligned and secured to the stools 7, 7 at the front of the furnace.

To operate the dampers 20, 20, I provide telescoped shafts 27, 27127", and 27, one for each set of the dampers. These are connected with their respective shafts by links 2.8, 28 and arms'28}. The shafts 27 etc. are

air to the ducts 10 from I accessible from" the front of the furnace and i heretofore used. Other and further advanta es of my invention will appear to those skilled in the art to which it relates.

I claim as my invention:

In a stoker, the combination of an endless chain grate having upper and lower leads, an upper set of cross-members dividing the space between said leads into a plurality of transverse compartments open to both leads, skids beneath the lower lead and extending lengthwise thereof for supporting the same, a lower set of cross-members beneath said skids and arranged transverse thereto in vertical alignment with the crossmembers of the upper set for supporting said skids, shoes bearing against said leads at both sets of cross-members, ducts at the sides of the grate and opening into said compartments for supplying draft thereto, a main supply conduit beneath said lower lead and common to all of said ducts, and a plurality of droppage collecting hoppers in the spaces between the lower cross-men1- bers, said hoppers being arranged one for each compartment and having outlets to discharge the droppage collected thereby.

In testimony that I claim the foregoing as my invention, I aflix my signature, this th day of January, A. D. 1923.

. THOMAS MARSH. 

